Method of making a line

ABSTRACT

A method of forming a line on a ground surface is described. It comprises the steps of: forming one or more slits in the ground surface; inserting a line of material in the or each slit such that part of the material is visible above the ground surface. Also described is a material suitable for use in forming a line on a ground surface. The ground surface is generally grassed earth, and the material can be a geotextile such as polypropylene. The present invention provides a simple but effective means of providing marked lines e.g. for playing surfaces such as football, rugby pitches and the like. The lines will remain, and need no further repair or maintenance for a number of years, while still providing the same visual effect as painted line.

The present invention relates to a method of making lines on ground surfaces suitable for playing fields and the like, and apparatus and material therefor.

In the island of Ireland, there are approximately 120,000 playing pitches for soccer, gaelic football, cricket and the like. The lines for such pitches are generally formed by a wheeled paint buggy, which introduces a line of paint on the ground through the travel of the front wheel through a paint reservoir.

However, heavily used pitches often require newly painted lines every week during a playing season, whereas these lines are often ‘lost’ in the non-playing season as the surrounding grass encroaches, and the pitches are not so regularly mowed. Weed or grass killer can be added to the intended line, but because grass is on either side of each line, the grass and weeds still encroach quickly. It will be appreciated the amount of time taken by groundsmen to keep clearing and repainting pitch lines for 120,000 pitches in Ireland alone.

It is an object of the present invention to provide more permanent lines in the ground.

Thus, according to one aspect of the present invention, there is provided a method of forming a line on a ground surface comprising the steps of: forming one or more slits in the ground surface; inserting a line of material in the or each slit such that part of the material is visible above the ground surface.

The slit in the ground surface could be formed by any suitable means, one such being a blade, preferably cylindrical, and preferably having a sharpened or tapered edge to assist entry into and through the ground surface.

The ground surface can be any surface on which a slit can be formed, one such being earth, more generally grassed earth.

In one embodiment of the present invention, the method comprises forming between two and four slits, preferably three slits, parallel in the ground, so as to create a broader form of ‘marked’ line. Where the method involves forming multiple lines, the lines can be any suitable distance apart. Where it is intended generally to provide a single visible marked line in the ground surface, the multiple slits are preferably relatively close, generally within 10-40 mm, and such as 20 mm, inter-distant.

The or each slit created preferably creates little or no visible disturbance on the ground surface other than the marked line. Preferably, the ground surface is rolled after the insertion of the or each line of material.

The material may be any suitable material, at least part of which is visible above the ground surface. The material may be any suitable colour, white being the commonest colour for many playing pitches. More than one colour could also be used, in any design or pattern.

Preferably, at least that part of the material visible above the ground surface is partially or at least substantially resistant to sunlight, in particular UV light. In this regard, the material may inherently have a high kilo-langley strength, or be treated so as to have such a high strength.

In another embodiment of the present invention, the material is at least partly open or has an open structure, through which the ground under the ground surface, or anything growing in the ground under the ground surface, such as the roots of grass, etc, can extend so as to help anchor the material in the slit either immediately and/or over time.

According to another embodiment of the present invention, the material is a polymer material such as polypropylene. Such material is widely available.

One range of polypropylene textile fibre materials are geotextiles. Such materials have moisture resistance so that water has no effect on tensile strength or mechanical properties, extensive chemical resistance, leachate compatibility, biological resistance as polypropylene does not support fungal growth, temperature stability, ultraviolet resistance (preferably by the addition of carbon black or other UV inhibitors), and superior puncture and Mullen burst strength (which make them resistant to installation stresses). One supplier of such materials is Don and Low Limited, Forfar, Scotland.

The material is preferably inserted in the slit by travel on the slit-forming means. More preferably, the material travels on the edge of the slit-forming means towards and into the surface, and is located in the slit as the slit is being formed.

More preferably, at least a portion of the material which is not inserted into the ground surface comprises a number of separate or discrete fibres, or fibre-like extensions. These together provide the visual form of the line, but are wholly or substantially individual like blades of grass. More preferably, that portion of the material above the ground surface is not damageable by a lawnmower or ground trimmer or the like.

The material could also include a herbicide, such as a weedkiller or the like, which preferably leaches from the material over time, and helps keep the area in and around the ground surface relatively clear. This includes grass.

According to one embodiment of the present invention, the material comprises a woven plastics material, having a central woven portion which is insertable in the ground surface, and extended weft fibres adapted to partially or substantially extended above the ground surface.

Thus, according to one embodiment of the present invention, there is provided a method of forming a line on a ground surface comprising the steps of: locating a slit-forming means having at least one blade on the ground surface, such that a portion of the blade enters the ground surface;

locating a fibrous or woven material on each blade; traversing the slit forming means along the path of the intended line;

allowing the material to travel with each blade into the ground;

leaving the material in each slit formed such that part of the material is visible above the ground surface.

According to a further embodiment of the present invention, the line formed by the present invention is ‘permanent’, i.e. remains to form a line for at least a number of years, expectantly greater than ten years.

The height of the material above the ground can be any suitable height, possibly based on expectation of use. For example, 30-35 mm height is generally suitable for many football pitches. Also, some ground surfaces are not flat, and the height of the visible material may be such as to be able to accommodate variation in the level of the surface.

In a second aspect, the present invention extends to a line on a ground surface formed by the method and/or material as hereinbefore described.

The method, and line thereby formed, may be straight or arcuate or any combination. The path of the line may follow guide means on the surface, or other markings.

When a straight line is desired, a direction means may be used, such a light beam, for example a laser beam. The beam could be directed along the intended path of the line, and that path then followed.

Thus, according to another embodiment of the present invention, the method further includes the step of following a light beam along the path of the intended line.

According to a third aspect of the present invention, there is provided a line-forming apparatus, which apparatus comprises one or more rotatable blades, each blade being adapted to form a slit in the ground surface, and adapted to feed around its edge a material for partially inserting into the slit.

Preferably the apparatus includes a roller following the or each blade, more preferably two or more rollers on which the apparatus traverses along the ground surface.

The apparatus could also include a line-direction means, or line-direction means receptor, such as a laser beam, or a laser beam screen. The user of the apparatus then follows the path of the beam to create a straight line.

According to a fourth aspect of the present invention, there is provided use of a material as hereinbefore defined to make a line on a ground surface.

The material could be made from any material including plastics. Preferably the material is a polyolefin such as polypropylene or a co-polymer, more preferably a geotextile.

According to a fifth aspect of the present invention, there is provided a vented fabric material suitable for use in forming a line on a ground surface.

Preferably, the vented fabric material comprises warp and weft fibres, having a core section or solid centre line, and free weft fibres or tapes on each side. The free weft fibres are designed to be that part of the fabric material that partially or substantially extends above the ground surface.

The material is preferably a woven plain material, more preferably a non-fibrolated tape. Typical but not-limiting qualities include 97 and 47 warp and weft ends per 10 cm, 125 g/m2 density, and 50 tex striped warp, and 220 tex white UV weft fibres.

The vented fabric material could be formed from a fully woven material, from which warp fibres are removed from each side to provide ‘free’ portions of the weft fibres.

Alternatively, and according to another aspect of the present invention, there is provided a process for forming a vented fabric material as herein before described, wherein lines of weft material are run, and intermittent lines of warp fibres are run thereinbetween, so as to form portions of woven material and portions of weft fibre material only.

Such a material can then be cut across each weft fibre portion, to create a vented fabric material having a woven core portion, and free weft fibres on each side.

Preferably, there is a catch thread included which holds the warp threads in place.

The process provides periodic weaving, or non-weaving, periods.

Embodiments of the present invention will now be described by way of example only, and with reference to the accompanying drawings in which:

FIG. 1 shows marked lines in a grassy earth surface according to one embodiment of the present invention;

FIGS. 2 a and 2 b are diagrammatic cross-sections of the ground in FIG. 1 along Arrows A & B respectively;

FIG. 3 is a side view of apparatus according to another embodiment of the present invention;

FIG. 4 is an enlarged part view of part of the apparatus in FIG. 3 in use;

FIG. 5 is a plan view of the apparatus in FIG. 3.

FIG. 6 is a schematic plan view of a vented fabric method of production according to another embodiment of the present invention; and

FIG. 7 is a section of vented fabric prepared from the process of FIG. 6.

Referring to the drawings, FIG. 1 shows marked lines 2 in a grassy earth-surface 4 as an illustration of the effect of the present invention. The marked lines could be used as pitch lines for the corner of a soccer or gaelic football pitch.

FIG. 2 a shows a cross-sectional view through the ground 4 across the path of the marked line 2 in FIG. 1, showing the location of three lines of white material 6 in the ground surface 4. FIG. 2 b shows a longitudinal cross-section of the marked line 2 of FIG. 1 along Arrow B. These figures show the material 6 having a woven section 10 which is within the ground surface 4, and the free fibres 12 extending therefrom, the ends of which 19 are visible above the ground surface 4.

That part of the material above the ground surface 4 is labelled in FIGS. 2 a and 2 b as 20, and that part which is below the ground surface 4 is labelled 22.

In FIG. 2 a, figurative grass 8 is shown each side of the line 2, although the relative heights of the grass 8 and the parts of the material above the ground surface 20 are for illustrative purposes only.

It is expected that the grass 8 will re-grow around the visible part 20 of the material. However, material such as polypropylene is not cuttable by most if not all types of lawnmowers, especially those lawnmowers used generally to mow playing surfaces. Thus, it is not a problem if the grass grows in amongst the visible material 20 creating the marked white lines, as mowing of the surface will reduce it to the same or a lower height than the visible (but free) polypropylene fibres 12, maintaining the visibility of the overall white line 2.

FIG. 3 shows apparatus comprising three cutting discs or blades 30. The blades 30 are rotatable about separate axles 32. The axles 32 are parallel and offset as shown in FIG. 5. The interdistance of the blades 30 could be approximately 20 mm apart, which distance is adjustable.

The three blades 30 are generally housed within a ballast frame 34. At the forward and rear ends of the frame 34 are round surface rollers 36. Above each blade 30 is a spool carrier 38, each having a spool tensioner 44.

Each blade 30 forms a slit in the ground surface 4 by traversing the ground surface 4, for example by being pulled by a tractor or the like through a linkage. As each blade 30 is pulled, it rotates about its axle 32, and so cuts through the ground surface 4.

Feeding onto each blade 30 from the associated spool carrier 38 and through weave tensioners 46 is a folded woven polypropylene material 40 approximately 200 mm wide, having a central woven band approximately 70-80 mm wide, and free weft fibres extending from each side of the central band. Example dimensions are 65/70/65 mm of free fibres and central core. The material 40 is shown diagrammatically in FIG. 3, but is the same as that shown in FIGS. 1, 2 a, 2 b and FIG. 7 hereinafter.

Fully woven polypropylene is used for forming bales or agricultural flexible sacks and the like.

The folding of the combined parts of the material 20, 22 in FIGS. 2 a and 2 b is better seen in FIG. 4. The folding is arranged to fit over the edge of a blade 30 as hereinafter described.

As the blades 30 rotate, the folded material 40 follows the edge of the blade 30 and is therefore fed into the ground surface 4 as the blade 30 enters also. The force of the blade 30 then locates the folded central woven section 10 of the material 40 in the slit formed, which part of the material 40 then remains in the ground surface 4 whilst the edge of the blade 30 exits the ground surface 4. The free ends 48 of the material 40, like those 20 in FIGS. 2 a and 2 b, are however now visible whilst being securely retained in the ground surface 4 as the ground folds back around the remaining part of the material and holds it in place. Over time, roots and the like can grow through the part of the material 22 in the ground surface 4, due to its open structure, increasing its securement in the ground.

Any ground disturbance caused by the slits is rolled by the rear roller 36.

In order to ensure straight lines, the apparatus or apparatus-pulling means, such as the tractor, could be laser guided by a laser set at the end of the intended path of the line, whose beam hits a receptor such as a screen on or near the apparatus etc. The screen is noted by the user in use, and the beam maintained within the screen, or limits set on the screen, to ensure the apparatus follows a straight line.

FIG. 6 shows a process for forming a vented fabric material as used in FIGS. 2 a and 2 b, etc wherein lines of weft threads 52 are constantly run, whilst only intermittent lines of warp threads 50 are run thereinbetween; the line of production being towards arrow C.

Once cut along the dashed line 54, two pieces of vented fabric material 56 one of which is shown in FIG. 7, is formed. Each piece 56 is useable for the method and with the apparatus hereinbefore described. That is, the extended or free weft threads 58 are the ‘free fibres’ 12, 48 shown in FIGS. 1, 2 a 2 b, 3 and 4, and the woven core 60 is the woven section 10, once the piece 56 is folded longitudinally in half.

The present invention has been found to lay the complete lines of the football pitch within a day, which lines then need no further maintenance or repair. Moreover, the free fibres 12, 48 extending above the ground surface will not trip or catch any player, such as by his boots studs. Moreover, the free fibres 12, 48 cannot be cut by a lawnmower such that mowing any playing pitch is not a problem.

Even if the fibres 12, 48, over time, are no longer. upstanding, they will generally maintain a visible area distinctive from the area therearound, such as grass. The fibres 12, 48 are also securely held in the ground surface 4, and cannot easily be pulled out as the fibres 12, 48 are only connected beneath the ground surface.

The present invention provides a simple but effective means of providing marked lines, which lines will remain, and need no further repair or maintenance for a number or years, while still providing the same visual effect as painted line. 

1-34. (canceled)
 35. A line forming apparatus for forming a line on the ground, said line forming apparatus comprising: a frame; at least one roller attachable to said frame, said roller being adapted to moveably support said frame over the ground; at least one disc rotatably attachable to said frame; at least one spool rotatably attachable to said frame; and a woven material associated with said spool and fed to said disc; wherein said disc being adapted to form a slit in the ground and feed said woven material into the slit.
 36. The line forming apparatus as set forth in claim 35 further comprising at least one spool tensioner associated with said spool.
 37. The line forming apparatus as set forth in claim 36 further comprising a weave tensioner adapted to have said woven material pass therethrough, said weave tensioner being positioned between said disc and said spool.
 38. The line forming apparatus as set forth in claim 35, wherein said disc is three offset and parallel rotatable blades, each having an associated spool, spool tensioner, and weave tensioner, and wherein said roller is two rollers, said rotatable blades being positioned between said rollers.
 39. The line forming apparatus as set forth in claim 35 further comprising a light guiding means for guiding said apparatus along a light path.
 40. The line forming apparatus as set forth in claim 35, wherein said woven material having a central woven band and free weft fibres extending from each side of said woven band, said free weft fibres being adapted to be visible above ground.
 41. The line forming apparatus as set forth in claim 40, wherein said woven material has an open structure, through which the ground under the ground surface, or anything growing in the ground under the ground surface, can traverse therethrough.
 42. The line forming apparatus as set forth in claim 41, wherein said free weft fibres of said woven material is substantially resistant to sunlight.
 43. The line forming apparatus as set forth in claim 35, wherein said woven material is made of polypropylene.
 44. A method of forming a line on the ground comprising the steps of: (a) providing a line forming apparatus comprising: a frame; at least one roller attachable to said frame, said roller being adapted to moveably support said frame over the ground; at least one disc rotatably attachable to said frame; at least one spool rotatably attachable to said frame; (b) providing a woven material associated with said spool; (c) traversing said line forming apparatus over the ground; (d) forming a slit in the ground by entering a portion of said disc into the ground; (e) feeding said woven material onto said disc; (f) inserting said woven material into the slit with said disc; (g) leaving said woven material in the slit; and (h) rolling the ground and the slit with said roller after said insertion of said woven material.
 45. The method of forming a line on the ground as set forth in claim 44, wherein said step (d) further comprising forming between two and four slits in the ground.
 46. The method of forming a line on the ground as set forth in claim 44, wherein said step (d) further comprising forming a plurality of slits, and the inter-distance between the slits is between 10 to 40 mm.
 47. The method of forming a line on the ground as set forth in claim 44, wherein said step (e) further comprising the step of folding said woven material over an edge of said disc.
 48. The method of forming a line on the ground as set forth in claim 47, wherein said woven material is folded equally on either side of the edge of said disc along a longitudinal central axis of said woven material.
 49. The method of forming a line on the ground as set forth in claim 44 further comprising, before said step (b), the step of forming a woven material by running lines of weft material, and running intermittent lines of warp fibres in between said lines of weft material, so as to form portions of woven material and portions of weft fibre material only.
 50. The method of forming a line on the ground as set forth in claim 49, wherein said step of forming a woven material further comprising the step of cutting across each weft fibre portion to create a vented fabric material.
 51. The method of forming a line on the ground as set forth in claim 44 further comprising the step of locating a light beam at one end of said line to be formed; and following the path of said beam.
 52. A method of forming a line on the ground comprising the steps of: (a) providing a line forming apparatus comprising: a frame; at least two rollers attachable to said frame, said roller being adapted to moveably support said frame over the ground; at least three offset and parallel rotatable blades attachable to said frame between said rollers, each of said blades having an associated spool, spool tensioner, and weave tensioner, said blades having tapered edges; (b) forming a woven material by running lines of weft material, and running intermittent lines of warp fibres in between said lines of weft material, so as to form portions of woven material and portions of weft fibre material only, then cutting across each of said weft fibre portions to create a vented fabric material; (c) associating said woven material with said spool; (d) feeding said woven material from said spools through said weave tensioners onto to said blades, wherein said woven material is folded equally on either side of said edges of said blades along a longitudinal central axis of said woven material; (e) traversing said line forming apparatus over the ground; (f) forming at least three slits in the ground by entering a portion of each of said blades into the ground; (g) inserting said woven material into the slits with said blades, wherein said woven material travels on said edges of blades towards and into the ground; (g) leaving said woven material in the slit; and (h) rolling the ground and the slit with said rollers before and after said insertion of said woven material.
 53. The method of forming a line on the ground as set forth in claim 52, wherein said step (f) the distance between the slits is between 10 to 40 mm.
 54. The method of forming a line on the ground as set forth in claim 52 further comprising the step of locating a light beam at one end of said line to be formed; and following the path of said beam. 